Syntheses of host molecules and evaluation for lithium ion recognition

Phosphate diesters，1a，1b，and1c，having p-叔butylcalic[4]arenes and alkyl groups(methyl，ethyl and propyl groups)as ester moieties were prepared.These compounds exist as an equilibrium of cone and partial-cone conformations in solution。However，the conformations of the calix[4]arene moieties in the Li and Na complexes of 1a as the methyl ester and/or 1b as the ethyl ester in solution are cone only，although that of the K complexes exist as a mixture of cone and partial-cone conformers。The compounds1a，1b，and1c showed selective complexation abilities toward the Li cation based on liquid membrane transport experiments。Liquid membrane transport abilities of alkali metal cations using1a depend upon the pH in the source phase.By increasing the pH，higher transport abilities for alkali metal cations and higher selectivity for Li I D1 I D 1 were observed。Furthermore，in order to obtain the phosphate ester having hexahomooxacalix[4]arene the reaction of hexahomooxacalix[4]arene with phosphorous tichloride was carried out。However the unexpected product was obtained.Therefore，the structure and formation mechanism of the unusual product were investigated in details。

Phosphate diesters, 1a, 1b, and 1c, having p-tert-butylcalic[4]arenes and alkyl groups (methyl, ethyl and propyl groups) as ester moieties were prepared. These compounds exist as an equilibrium of cone and partial-cone conformations in solution. However, the conformations of the calix[4]arene moieties in the Li and Na complexes of 1a as the methyl ester and/or 1b as the ethyl ester in solution are cone only, although that of the K complexes exist as a mixture of cone and partial-cone conformers. The compounds 1a, 1b, and 1c showed selective complexation abilities toward the Li cation based on liquid membrane transport experiments. Liquid membrane transport abilities of alkali metal cations using 1a depend upon the pH in the source phase. By increasing the pH, higher transport abilities for alkali metal cations and higher selectivity for LiィイD1+ィエD1 were observed. Furthermore, in order to obtain the phosphate ester having hexahomooxacalix[4]arene the reaction of hexahomooxacalix[4]arene with phosphorous tichloride was carried out. However the unexpected product was obtained. Therefore, the structure and formation mechanism of the unusual product were investigated in details.